It sounds as though you are teetering on the verge of a crash. I too have a P4S533 with Corsair XMS PC3200 RAM. I can only set the cpu/memory frequency to Auto or 1:1 with any kind of stability. I would recommend the same and hope a BIOS upgrade will be available soon. I am running a dual boot with Win2k and WinMe and indeed WinMe is more stable.
To start press any key. Where's the "any" key? --Homer Simpson.